org.apache.tools.ant.types.selectors

Class DifferentSelector

Implemented Interfaces:
FileSelector

public class DifferentSelector
extends MappingSelector

This selector selects files against a mapped set of target files, selecting all those files which are different. A byte-by-byte comparision is performed on equal length files; files with different lengths are deemed different automatically; files with identical timestamps are viewed as matching by default, unless you specify otherwise.

This is a useful selector to work with programs and tasks that don't handle dependency checking properly; Even if a predecessor task always creates its output files, followup tasks can be driven off copies made with a different selector, so their dependencies are driven on the absolute state of the files, not a timestamp.

Clearly, however, bulk file comparisons is inefficient; anything that can use timestamps is to be preferred. If this selector must be used, use it over as few files as possible, perhaps following it with an <uptodate;&gt to keep the descendent routines conditional.

Field Summary

Fields inherited from class org.apache.tools.ant.types.selectors.MappingSelector

granularity, map, mapperElement, targetdir

Fields inherited from class org.apache.tools.ant.types.DataType

checked, description, ref

Fields inherited from class org.apache.tools.ant.ProjectComponent

project

Method Summary

protected boolean
selectionTest(File srcfile, File destfile)
this test is our selection test that compared the file with the destfile
void
setIgnoreFileTimes(boolean ignoreFileTimes)
This flag tells the selector to ignore file times in the comparison

Methods inherited from class org.apache.tools.ant.types.selectors.MappingSelector

createMapper, isSelected, selectionTest, setGranularity, setTargetdir, verifySettings

Methods inherited from class org.apache.tools.ant.types.selectors.BaseSelector

getError, isSelected, setError, validate, verifySettings

Methods inherited from class org.apache.tools.ant.types.DataType

checkAttributesAllowed, checkChildrenAllowed, circularReference, dieOnCircularReference, getCheckedRef, getDescription, getRefid, isChecked, isReference, noChildrenAllowed, setChecked, setDescription, setRefid, tooManyAttributes

Methods inherited from class org.apache.tools.ant.ProjectComponent

getProject, log, log, setProject

Method Details

selectionTest

protected boolean selectionTest(File srcfile,
                                File destfile)
this test is our selection test that compared the file with the destfile
Overrides:
selectionTest in interface MappingSelector

Parameters:
srcfile - the source file
destfile - the destination file

Returns:
true if the files are different


setIgnoreFileTimes

public void setIgnoreFileTimes(boolean ignoreFileTimes)
This flag tells the selector to ignore file times in the comparison

Parameters:
ignoreFileTimes - if true ignore file times


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